1. Technical Field
The present invention relates to technologies for controlling a display device that uses data of a-gradation levels to display an image with b-gradation levels.
2. Related Art
Display devices using display elements such as electrophoretic elements are known. It has been known that, when a pixel is rewritten from one gradation level (for example, white) to another gradation level (for example, black), gradation blurring-out occurs at pixels adjacent to the pixel rewritten. Japanese Laid-open Patent Application 2007-206267 describes a partial rewriting operation for alleviating afterimages upon erasure that occur at the time of image switching.
However, even when the partial rewriting operation is performed, gradation blurring-out may occur at pixels adjacent to rewritten pixels. The gradation blurring-out of this kind affects gradations to be actually displayed at a display device when halftones are to be displayed by a color reduction process using a dither matrix.